Such a device for extracting a cardiac pacemaker electrode which has grown onto the heart by means of cardiac pacemaker electrode cable with a spiral coil is known from the international patent application WO 91/19532 A1 and has an anchoring part in the form of a split tube segment connected to the distal end of the cable and whose ends facing the tube have been slightly pre-spread towards the outside. By pulling on the cable, the pre-spread, split tube segment is activated, the tube segment halves are spread apart and their free ends engage in the inner side of the spiral coil of the electrode cable.
In a device of this type, depending on the diameter of the inner lumen of the electrode cable, different sizes must be provided for the anchoring part of the extraction device. Another disadvantage is that in case the diameter of the inner lumen is too large, the tube segment halves can fold, as a result of which safe anchoring is no longer ensured.
In addition, such an extraction device only works reliably with multiple-coil electrodes, in particular four-coil electrodes.
U.S. Pat. No. 5,632,749 also describes a device of above type in which the anchoring part is a split sleeve which can be activated by means of a relative motion between the tube and the cable. The sleeve is split along its longitudinal axis and designed in such a way that its diameter can be enlarged for the purpose of activating the device. For that purpose, on the distal end of the tube as well as on the distal end of the cable, conical surfaces facing each other are provided which can be engaged by pulling the cable, causing the split sleeve to enlarge and press against the spiral coil of the electrode cable along a large number of coils in order to achieve traction. Such a type of device has the disadvantage that sufficient traction requires large axial forces on the split sleeve by pulling the cable and holding against it with the tube. Another disadvantage is that only a relatively small enlargement of the diameter of the split sleeve is possible, as a result of which, depending on the diameter of the inner lumen of the spiral coil of the cardiac pacemaker cable, different sizes of extracting devices must be available.